diff options
| author | Florian Westphal <fw@strlen.de> | 2024-11-04 10:41:19 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2024-11-05 22:07:12 +0100 |
| commit | cddc04275f95ca3b18da5c0fb111705ac173af89 (patch) | |
| tree | 327062f50e9ff4416b016b4b40e6610178cec9ad | |
| parent | ee666a541ed957937454d50afa4757924508cd74 (diff) | |
netfilter: nf_tables: must hold rcu read lock while iterating object type list
Update of stateful object triggers:
WARNING: suspicious RCU usage
net/netfilter/nf_tables_api.c:7759 RCU-list traversed in non-reader section!!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by nft/3060:
#0: ffff88810f0578c8 (&nft_net->commit_mutex){+.+.}-{4:4}, [..]
... but this list is not protected by the transaction mutex but the
nfnl nftables subsystem mutex.
Switch to nft_obj_type_get which will acquire rcu read lock,
bump refcount, and returns the result.
v3: Dan Carpenter points out nft_obj_type_get returns error pointer, not
NULL, on error.
Fixes: dad3bdeef45f ("netfilter: nf_tables: fix memory leak during stateful obj update").
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | net/netfilter/nf_tables_api.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index de8e48a5c62d..b7a817e483aa 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -7809,9 +7809,7 @@ static int nf_tables_updobj(const struct nft_ctx *ctx, struct nft_trans *trans; int err = -ENOMEM; - if (!try_module_get(type->owner)) - return -ENOENT; - + /* caller must have obtained type->owner reference. */ trans = nft_trans_alloc(ctx, NFT_MSG_NEWOBJ, sizeof(struct nft_trans_obj)); if (!trans) @@ -7879,15 +7877,16 @@ static int nf_tables_newobj(struct sk_buff *skb, const struct nfnl_info *info, if (info->nlh->nlmsg_flags & NLM_F_REPLACE) return -EOPNOTSUPP; - type = __nft_obj_type_get(objtype, family); - if (WARN_ON_ONCE(!type)) - return -ENOENT; - if (!obj->ops->update) return 0; + type = nft_obj_type_get(net, objtype, family); + if (WARN_ON_ONCE(IS_ERR(type))) + return PTR_ERR(type); + nft_ctx_init(&ctx, net, skb, info->nlh, family, table, NULL, nla); + /* type->owner reference is put when transaction object is released. */ return nf_tables_updobj(&ctx, type, nla[NFTA_OBJ_DATA], obj); } |